This invention relates generally, as indicated, to a nose landing gear jump strut assembly for high performance aircraft such as operated by the military, to provide reduced take-off ground roll and/or overload capability for such aircraft.
There are occasions when it would be desirable to provide high performance military aircraft and the like with the capability of taking off in shorter distances than normal or of increasing the payload capability without increasing the distance required to take off.
It is generally known that such aircraft could take off in shorter distances at lower ground speeds or that the payload capability of the aircraft could be increased without increasing the take-off ground roll of the aircraft if the nose of the aircraft were somehow raised sooner than normal to increase the angle of attack and thus the lift of the aircraft. One way to do this is to provide the aircraft with a longer nose strut to raise the nose of the aircraft up. However, this has the disadvantage of putting the aircraft in a relatively high drag attitude during the entire take-off run.
Another way, which is disclosed in U.S. Pat. No. 4,524,929, is to restrain the landing gear strut in a shortened condition during the initial portion of the take-off ground run and then release the strut to permit high internal pressure within the interior of the strut to expand the strut and rotate the airplane to a high angle of attack appropriate for take-off. Although this substantially eliminates the high drag problem previously mentioned, it has the disadvantage that the strut cannot perform the usual energy dissipating functions during any portion of the take-off ground run.